Additive manufacturing apparatus

ABSTRACT

A CNC machine including a worktable displaceable along a y-axis, a gantry disposed along an x-axis, either fixed or displaceable along the y-axis, a carriage on such gantry displaceable along the x-axis and including a thermoplastic material extrusion conduit, a tool carrier mounted on such carriage displaceable along a z-axis, a dispersion conduit mounted on such tool carrier accommodating an applicator, means mounted on such applicator for extruding a molten bead of a thermoplastic material, a flexible hose interconnecting such molten material forming means and such applicator, a plurality of servomotors for linearly or rotationally displacing such components along or about such axes and a computer for controlling such component displacements.

This invention relates to an apparatus for forming a configured articleand more particularly to such an apparatus provided with improved meansfor effectively and economically forming such article by an extrusionprocess.

BACKGROUND OF THE INVENTION

In the prior art, there has been developed a process commonly referredto as an additive manufacturing process which generally consists offorming various bodies by extruding a bead of a molten thermoplasticmaterial, applying such bead of molten material in a strata of layers toform a replica of an article sought to be formed and then machining suchreplica when cooled to remove excess material and provide the finalconfiguration of the intended article, in practicing such process,several aspects thereof have been noted. In procedures where thick beadsof molten material are produced, it has been found that an oversizedreplica of the intended article results, requiring excessive machiningin producing the final article configuration, requiring increasedproduction time and excessive scarp material. In forming comparativelylarge articles, it further has been found that lain strata of extrudedmaterial are apt to cool thereby impairing the fusion of a layer ofmolten material applied thereon. Such lack of fusion may be overcome bytamping an overlying, molten bead segment to induce fusion. Suchremedial measure however, has the effect of causing the bulging ofapplied layers, often requiring additional machining. In seeking toovercome the disadvantages of the use of thick beads of molten material,thin beads of material have been employed. Such use has been effectivein reducing machine time but results in a substantial increase inoverall production time thereby negatively affecting productively.

In view of the foregoing, it is the principal object of the presentinvention to provide an improved apparatus for producing an articlethrough the use of an additive material process, requiring little if anymachining of a molded body in providing a final product.

BRIEF DESCRIPTION OF THE INVENTION

The principal object of the present invention is achieved by anapparatus including a worktable supported on a bed, having a supportsurface disposed in an x-y plane, disposed in one of a fixed conditionon such bed and a displaceable condition along a y-axis; a gantrysupported on such bed along an x-axis, disposed in one of a fixedcondition on such bed with a worktable displaceable along the y-axis anda displaceable condition along the y-axis on such bed with suchworktable disposed in a fixed condition on such bed; a carriage mountedon such gantry, displaceable along a y-axis, provided with means forforming a molten thermoplastic material extrudable through an outletconduit thereof; a tool carrier mounted on such carriage, displaceablealong a z-axis; a tool holder mounted on such tool carrier, rotatablydisplaceable about a z-axis; a tool support shaft provided with an axisdisposed in an x-y plane, journaled in such tool holder and rotatablydisplaceable about the axis thereof; a dispenser conduit mounted on suchtool support shaft, disposed perpendicularly relative to the axisthereof, accommodating a nozzle at an outlet end thereof; meansmountable on such dispenser conduit for applying a formed, molten beadof a molten thermoplastic material; a flexible hose provided with afirst end supported on such tool conduit of the material extrusionmeans, and a second end attached to an inlet of the dispenser conduit; aplurality of servomotors each operatively connected to one of suchaforementioned components for selectively displacing such one componentin one of a rotational and linear movement; and a control computeroperatively connected to such servomotors for operation in execution ofa program inputted into the control thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a CNC machine incorporating the presentinvention;

FIG. 2 is an enlarged perspective view of the carriage shown in FIG. 1illustrating the tool carrier and holder portions thereof, havingportions thereof broken away;

FIG. 3 is a perspective view of the carriage shown in FIG. 2illustrating the use of the invention in forming an article;

FIG. 4 is a view similar to the view shown in FIG. 2 having portionsthereof broken away to more fully illustrate the connections of certaincomponents thereof;

FIG. 5 is a perspective view of a storage rack provided on the worktableof the machine shown in FIG. 1, accommodating a number of applicatorcomponents, each provided with a material applying channel having aunique cross-sectional configuration;

FIG. 6 is a perspective view of a holding bracket of the rack shown inFIG. 5, illustrating the manner by which a detachable applicatorcomponent of a device as shown in FIGS. 1 through 4 may be displaced toattach to and be displaced from a selected rack;

FIG. 7 is vertical, cross-sectional view of an article formed by amachine in the use of a conventional additive manufacturing process;

FIG. 8 is a vertical, cross-sectional view of an article formed by theuse of the present invention; and;

FIG. 9 is a perspective view of a portion of the present inventionillustrating the formulation of a portion of the hull of a watercraft,having a portion thereof broken away.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

Referring to FIG. 1 of the drawings, there is illustrated a CNC machinewhich embodies the present invention, Such machine includes a bed 20, aworktable 21 having a support surface lying in an x-y plane, mounted ona set of guide rails 22 and 23 and displaceable along a y-axis by a pairof servomotors drivingly connected thereto, a gantry 24 provided with apair of laterally spaced legs 25 and 26 supported on bed 20, a carriage27 mounted on a set of guide rails 28, 29 and 30 provided on the gantryand displaceable along an x-axis by a servomotor mounted on the gantry,drivingly connected thereto and a tool carrier 31 and tool holder 32mounted on a set of guide rails 33 and 34 provided on carriage 27 anddisplaceable along a z-axis by a servomotor mounted on carriage 27 anddrivingly connected thereto. Such carriage further is provided with amaterial dispenser 35. Each of such servomotors is operatively connectedto a control computer disposed on or in the vicinity of such machine,functional in executing imputed programs for displacing such componentsalong such x, y and z axes.

As best shown in FIGS. 2 and 4, carrier 31 includes a verticallydisposed housing 36 provided with a support platform 37 having anopening therein disposed along a z-axis. Mounted on the upper side ofplatform 37 is a gear box 38 provided with an opening 39 verticallyaligned with the opening in the support platform. Disposed on theunderside of platform 37 is a rotable mounting platform 40 having anopening therethrough coaxial with the opening in platform 37 and gearbox38, and connected to an annular flange of a depending drivable conduitof gearbox 38. Further mounted on support platform 37 is a servomotor 41provided with an outlet shaft operatively connected to gearbox 38 forimparting rotational drive to mounting platform 40.

Tool holder 32 depends from carrier 31 and is rotatably displaceablerelative thereto about the z-axis of gear box 38 and mounting platform40. it includes an upper segment 42 connected to mounting platform 40,provided with an opening therethrough coaxially disposed with respect tothe aligned openings in gearbox 38, support platform 37 and mountingplatform 40, and a depending segment 43 spaced laterally of the z-axisof rotation of platform 40. Mounted on an inner side of segment 43 is agearbox 44 provided with an output shaft 45 having an axis of rotationlying in an x-y plane intersecting the z-axis of rotation of the toolholder. Such shaft is rotatably displaceable about its axis by means ofa servomotor 46 mounted on the depending segment of the tool holder,operatively connected to gearbox 44. Also, mounted on the end of outputshaft 45 is a support conduit 47 provided with an axis intersecting boththe axis of rotation of shaft 45 and the z-axis of rotation of the toolholder, arid a bearing 48.

As best shown in FIG. 3, an extruder 50 of a molten thermoplasticmaterial is provided in an upper portion of housing 31, along the z-axisof the openings in the tool carrier and tool holder. Such extruderincludes an upper cylindrical portion 51 provided with a heater and anextruding mechanism for forming and extruding therefrom a moltenthermoplastic material, through a lower funnel portion 52 and an outlettube 53 disposed along the z-axis of the aligned openings in gearbox 37,support platform 37 and rotatable platform 40. An annular collar 54further is provided at the outlet end of tube 53.

Material applicator 35 as best shown in FIG. 4 includes an insulated,flexible conduit 60 provided with a metallic rim 61 at one end thereofand a rigid, metallic dispenser conduit 62 at the other end thereof.

Mounted concentrically with request to z-axis, on bearing box 38 is anannular base member 63, on which an annular swivel member 64 isrotatably mounted. Rim 61 of hose 60 is rigidly, concentricallyconnected to swivel member 64 and forms a rotatable union with collar 54of extruder outlet conduit 53 of extruder 50 to provide a moltenmaterial path into and through the upper end of flexible hose 60. Theother end of hose 60 is connected to an inlet end of dispenser 62through an adapter 65. Swivel member 64 along with fixedly mounted tuberim 61 are rotatably displaceable between base member 63 and extrudertube collar 54 by means of a servomotor 66 mounted in support platform37 and a pulley 67 entrained about a sheave provided on the output shaftof motor 66 and a sheave portion of swivel member 64. Servomotors 41, 46and 66 also are operated by the control computer pursuant to theexecution of an inputted program.

Mounted on the fee end of disperser tube 62 is a material applicatordevice 70 including a base component 71 and a detachable component 72 ofa type as illustrated and described in U.S. patent application Ser. No.______, filed ______ 2015. Generally, component 72 includes an annularsegment 73 provided with an annular recess 74 with an axial openingtherethrough, and a molten material shaping segment 75 provided with amaterial guide channel 76, and component 71 which includes a tubularsegment 77 insertable in dispenser tube 62, and an appendage segment 78detachably receivable in the recessed segment of component 72, providedwith an opening communicable with the axial passage in component 72 andmeans for detachably connecting such components together as shown inFIG. 6.

An array of components 72, each provided with a differently configuredguide channel 76, is provided, mounted on an array of holders 79positioned on the bed of the machine, as shown in FIGS. 1 and 6,accessible to the tool holder. A leading edge of the top wall of eachholder 79 is provided with a recess 80 adapted to receive and support asegment 73 of a component 72. Each segment 73 is provided with aparallel set of laterally opening slots, in the sides thereof, adaptedto receive the opposed side edges of the recess of a holder when suchsegment is slid into such recess to mount on a holder as further shownin FIG. 5. An electrically heated strip 81 also is provided on themachine bed below overextending portions of the top walls of holders 79,functional in maintaining stored segments 72 heated in accommodating theflow of heated material when in use.

In the use of the machine as described to form an article eitherdirectly on the workable thereof or on a mold mounted thereon, a supplyof pellets of a thermoplastic material is fed into extruder 50, and asuitable program is inputted into the central system of the computer.Upon operation of the machine, the control system will function to heatand churn the extruder to form a molten thermoplastic material, andtimely execute the inputted program in causing molten material to flowthrough flexible tube 60, applicator conduit 62 and dispensing device70, and operate the several servomotors to displace device 70 linearlyalong the x, y and z-axes, rotatably about the x axis the axes of shaft45 and applicator conduit 62 and combinations of such displacements,pursuant to the inputted program, in directing the application ofextruded molten material in plies forming the configuration of anintended article. In the course of such operation in which a particularcross-sectional configuration of one or more plies may be required, theprogram will provide for maneuvering the tool carrier and holder toreplace a mounted forming segment 72 by mounting an attached formingsegment on a vacant holder 79 and attaching another segment 72 providedwith a different, selected cross-sectional configuration.

In the use of the machine as described, the plies of molten materialdeposited in forming the configuration of a particular article, are notapplied in strata disposed exclusively in x-y planes as illustrated inFIG. 7, which is characteristic of prior art additive manufacturingmachine processors requiring the use of excess material and subsequentmaterial removal but are applied in continuous linear and curved linesas shown in FIGS. 3 and 8, requiring less material and less if anymaterial removal. The machine as described further may be employed toform a curved structure such as the hull of a boat as shown in FIG. 9provided with a worktable perhaps provided with a suitably contouredrecess provided with a suitable coating material.

From the foregoing detailed description, it will be evident that thereare a number of changes, adaptations and modifications of the presentinvention, which come within the province of those persons havingordinary skill in the art to which the aforementioned inventionpertains. However, it is intended that all such variations not departingfrom the spirit of the invention be considered as within the scopethereof as limited solely by the appended claims.

I claim:
 1. A CNC machine operable in producing an article of a selectedconfiguration, comprising: a worktable supported on a bed, having asupport surface disposed in an x-y plane, disposed in one of a fixedcondition on said bed and a displaceable condition along a y-axis; agantry supported on said bed along an x-axis, disposed in one of a fixedcondition on said bed with a worktable displaceable along the y-axis anda displaceable condition along the y-axis on said bed with saidworktable disposed in a fixed condition on said bed; a carriage mountedon said gantry, displaceable along an x-axis, provided with means forforming a molten thermoplastic material extrudable through an outletconduit; a tool carrier mounted on said carriage, a displaceable along az-axis; a tool holder mounted on said tool carrier, rotatablydisplaceable about a z-axis; a tool support shaft provided with an axisdisposed in an x-y plane, journaled in said tool holder and rotatablydisplaceable about the axis thereof; a dispenser conduit mounted on saidtool support shaft, disposed perpendicularly relative to the axisthereof accommodating an applicator at an outlet end thereof; meansmountable on said applicator conduit for extruding through an outletthereof a, molten bead of a molten thermoplastic material; a flexiblehose provided with a first end supported on said tool carrier, forming arotary union with said outlet conduit of said material extruding means,and a second end communicating with and attached to an inlet end of saiddispenser conduit; a plurality of servomotors each operatively connectedto one of said aforementioned components for selectively displacing saidcomponent one of a rotational and linear movement; and computerfunctional pursuant to the execution of an inputted program foroperatively controlling said servomotors.
 2. The machine according toclaim I wherein said worktable is displaceable along a set of railsprovided on said bed and is displaceable by at least one servomotormounted on said bed, having a threaded output shaft received in athreaded opening of said worktable.
 3. The machine of claim 1 whereinsaid gantry in displaceable along a set of rails provided on said bedand is displaceable by at least one servomotor mounted on said bed,having a threaded output shaft received in a threaded opening in asupport portion of said gantry.
 4. The machine of claim 1 wherein saidcarriage is displaceable along a set of rails provided on said gantryand is displaceable along said set of rails by at least one servomotormounted on said gantry, having an output shaft threadedly engageablewith a portion of said carriage.
 5. The machine of claim 1 wherein saidtool holder is pivotally connected to and dependant from a bottom wallof said carriage and is rotatably displaceable by a servomotor mountedon said bottom wall having a shaft with a gear engaging a gear of saidtool holder.
 6. The machine of claim 1 wherein the axis of said toolsupport shaft of said tool holder is disposed in an x-y plane andintersects the axis of rotation of said tool holder, and said shaft isrotatably displaceable about it axis by a servomotor mounted on saidtool holder, provided with an output shaft having a gear meshing with agear of said tool support shaft.
 7. The machine of claim 1 wherein saiddispenser conduit is journaled within a bearing disposed in acylindrical member mounted perpendicular to the axis of said toolsupport shaft.
 8. The machine of claim 1 wherein said means mountable onsaid applicator conduit for extruding through an outlet thereof a moltenbead of a pliable thermoplastic material, includes means for shaping thecross-sectional configuration of said molten bead.
 9. The machine ofclaim 1 wherein the axis of rotation of said tool carrier, the axis ofsaid tool support shaft and the axis of said dispenser conduitintersect.
 10. The machine of claim 8 including a selected number ofsegments of said applicator means mountable on said dispenser conduitsupported on said bed, selectively attachable to said dispenser conduitwherein each of said mountable means is provided with unique means forshaping the cross sectional configuration of said molten bead.
 11. Themachine of claim 4 wherein said carriage includes: a bottom platformwall provided with an opening disposed along a z-axis; an extruderdisposed above said platform wall provided with an outlet disposed alongsaid z-axis; an annular, swivable member supported on said platform wallconcentric with said extruder outlet, along said z-axis; and meanssupported on said platform wall for incrementally rotatably displacingsaid swivable member, wherein an end of said flexible hose is connectedconcentrically with said swivel member, forming a rotary union with saidextruder outlet, providing a passageway from said extruder into saidflexible hose along said z-axis.
 12. The machine of claim 11 whereinsaid extruder includes a heatable cylindrical member supported on saidcarriage along said x-axis, provided with said outlet at a lower endthereof communicating with said flexible conduit through a rotary union,and a notable helical member disposed therein along said z-axis,functional upon feeding particles of a thermoplastic material into saidcylindrical member, heating said cylindrical member and rotating saidhelical member, to extrude a bead of molten thermoplastic material intosaid flexible hose.
 13. The machine of claim 11 wherein said meanssupported on said platform wall incrementally rotatably displacing saidswivable member comprises a servomotor mounted on said platformdrivingly connected to said swivel member by means of a pulley.
 14. Themachine of claim 5 wherein said tool holder includes a first segmentpivotally mounted on the underside of a bottom wall of said carriage forrotation about said z-axis, provided with an opening therein alignedwith an opening in said bottom wall for receiving a portion of saidflexible hose therethough, and a second segment depending from saidfirst segment, spaced laterally of said z-axis and supporting said toolsupport shaft
 15. The machine of claim 6 including a support conduitdisposed on the end of said tool support shaft, having an axis disposedperpendicularly relative to the axis of said shaft, and a bearingdisposed in said support conduit wherein said dispenser conduit isjournaled in bearing of said support conduit
 16. The machine of claim 1wherein said flexible hose is rotatable about a centerline thereofformed of a heat retentive material, has a first end projecting throughan opening in said carriage and connected to an outlet of an extruder ofa bead of heated, molten thermoplastic material by means of a rotaryunion, and a second end provided with an applicator conduit journaled ina bearing disposed on said tool support shaft.
 17. The machine of claim16 including an applicator provided with a first segment mounted on saiddispenser conduit, having an opening therethrough communicating with thepassageway of said dispenser conduit, and a second segment detachablyconnected to said first segment, provided with a bead forming channelhaving an inlet communicable with said first segment opening when saidsecond segment is attached to said first segment, and a selectedcross-sectional configuration.
 18. The machine of claim 17 including atleast two of said second segments, each provided with bead formingchannel of a unique cross-sectional configuration.
 19. The machine ofclaim 18 including means disposed on said machine for storing saidsecond applicator segments, accessible by said first applicator segmentfor attaching and detaching a selected one of said second applicatorsegments.
 20. The machine of claim 17 wherein one of said applicatorsegments includes a recess and the other of said applicator segments isprovided with a portion nestable in said recess in said other applicatorsegment, wherein said recess and nestable portion are provided with atleast one spring loaded plunger on one of said segments cooperable witha mating recess in the other of said nestable segments to detachablysecure said nested segments together.
 21. An assembly mountable on amachine provided with a worktable supported on a bed, having a supportsurface disposed in an x-y plane, disposed in one of a fixed conditionon said bed and a displaceable condition along a y-axis, a gantrysupported on said bed along an x-axis, disposed in one of a fixedcondition on said bed with a worktable displaceable along a y-axis and adisplaceable condition along the y-axis on said bed with said worktablein a fixed condition, comprising: a carriage mountable on said gantry,displaceable along a y-axis, provided with means for forming a moltenthermoplastic material extrudable through an outlet conduit; a toolcarrier mounted on said carriage, displaceable along a z-axis; a toolholder mounted on said tool carrier, displaceable about a z-axis a toolsupport shaft provided with an axis disposed in an x-y plane, journaledin said tool holder and rotatably displaceable about the axis thereof;an dispenser conduit mounted on said tool support shaft, disposedperpendicularly relative to the axis thereof; means mountable on saiddispenser conduit for ejecting through an outlet thereof, a formed,molten beam of a thermoplastic material; and a flexible hose providedwith a first end supported on said tool carrier, forming a rotary unionwith said molten material extrusion conduit, and a second endcommunicating with and attached to an inlet of said dispenser conduit;wherein said carriage is operatively connectable to means fordisplacement thereof along said y-axis, said tool holder is operativelyconnectable to means for rotary displacement about said z-axis, saidtool support shaft is operatively connectable to means for rotarydisplacement about its axis and said flexible hose is operativelyconnectable to means for rotary displacement about its centerline. 22.The assembly of claim 21 wherein said carriage includes: means forholding particles of a thermoplastic material, having an outlet; meansfor heating said particles to form a molten material; and means forextruding said molten material through said outlet into and through saidflexible hose,
 23. The assembly of claim 21 wherein said tool carrierincludes; a bottom platform wall provided with an opening along anz-axis; an annular, swivable member supported on said platform wallconcen with said extruder outlet and said platform wall opening; andmeans supported on said platform wall for incrementally ratablydisplacing said swivable member, wherein an end of said flexible hose isreceived through said platform wall opening and connected concentricallywith said swivel member, forming a rotary union with said extruderoutlet, providing a passageway from said extruder into and through saidflexible hose.
 24. The assembly of claim 23 wherein said means supportedon said platform wall incrementally rotatably displacing said swivablemember comprises a servomotor mounted on said platform drivinglyconnected to said swivel member by means of a pulley.
 25. The assemblyof claim 21 wherein said tool holder includes: a member including afirst segment pivotally connected and depending from a bottom wall ofsaid carriage and rotably displaceable about said z-axis, having anopening therein communicating with said opening in said carriage bottomwall, along said z-axis, and a second segment projecting downwardly fromsaid first segment and spaced laterally of said z-axis; and meansmounted on said bottom wall of said carriage operatively connected tosaid first segment for ratably displacing said depending member.
 26. Theassembly of claim 25 wherein said means for rotably displacing saiddepending member includes a servomotor supported on said carriage bottomwall, drivingly connected to said first segment of said depending memberthrough a gear assembly.
 27. The assembly of claim 2? wherein said toolsupport shaft is journaled in a depending segment of said tool holderspaced laterally of said z-axis, and said means operatively connectableto means for rotably displacement about its axis includes a servomotormounted on said tool holder drivingly connected to said tool supportshaft through a gear assembly
 28. The assembly of claim 21 wherein saidfirst end of said flexible hose extends through an opening in saidcarrier bottom wall disposed along said z-axis, is connected to a swivelsupported on said carrier bottom wall and ratable about said z-axis, andconnected to said molten material extrusion conduit by means of a rotaryunion disposed along said z-axis; and said second end of said flexiblehose includes said applicator conduit journaled in a bearing disposed ina conduit mounted on said tool support shaft perpendicularly relative tothe axis thereof.
 29. The assembly of claim 28 including means forselectively rotably displacing said swivel member, imparting arotational displacement of said first end of said flexible hose withinsaid rotary union with said molten material extrusion conduit andcorresponding rotational displacement of said applicator conduitdisposed on said second end of said flexible hose, journaled in saidbearing disposed in said conduit mounted on said tool support shaft. 30.The assembly of claim 29 wherein said means for selectively rotablydisplacing said swivel member includes a servomotor supported on saidtool carrier and a drive pulley trained about an output of saidservomotor and an input of said swivel member.